This invention relates in general to carburetors for internal combustion engines and, more particularly, to carburetors incorporating sonic throats.
Many efforts have been made to design a sonic throat carburetor which will effectively produce a better fuel-air mixture and a more even mixture flow to the cylinders of internal combustion engines than carburetors of conventional design. One of the primary reasons for the lack of success of adapting the sonic principle to carburetors is believed to be the inability of providing flow stability in the diffuser section downstream of the sonic throat. Considerable difficulty is customarily encountered in obtaining a stable flow in the diffuser section since the flow will normally tend to separate from one circumferential or transverse zone immediately downstream of the sonic throat to the next succeeding zone and thereby cause exceedingly large nonuniformities in the diffusing flow. Thus, undesired instabilities, such as nonuniform flow, pulsating flow, and nonuniform fuel air mixtures are caused.
The present invention overcomes these recognized disadvantages by providing a carburetor having a sonic throat, but wherein the components defining such throat may be relatively moved, one with respect to the other, for altering the cross section of the throat in correspondence to the power requirements as the carburetor throttle is actuated from an idle position. Additionally, the components defining the sonic throat are provided with a multiplicity of indentations, projections, or surface irregular zones, producing a pattern of small, interlaced, and interacting shock waves conducing to stability of flow in the diffuser section, said waves thus effecting a smooth transistion from supersonic to subsonic flow. The incorporated indentations, projections, or surface irregularities will bring about a flow stability together with a more uniform air fuel mixture and thereby overcome the drawbacks which have been posing a continual problem to the use of sonic throat carburetors to the present time.
Therefore, it is an object of the present invention to provide a carburetor incorporating a sonic throat which is adapted to promote stability of flow in the diffuser section.
It is another object of the present invention to provide a carburetor of the character stated which incorporates uniquely adapted components for altering the cross section of the carburetor throat responsive to particular power requirements of the associated engine at a given juncture.
It is a further object of the present invention to provide a carburetor of the character stated which embodies novel improvements to sonic throat-defining surfaces for creating zones of turbulence to facilitate the transistion of flow from supersonic to subsonic and which promote a substantially uniform air-fuel mixture.
It is another object of the present invention to provide a carburetor of the type stated which is adapted to eliminate pulsating flow within the diffuser section.
It is a still further object of the present invention to provide a carburetor of the type stated which is capable of delivering a uniformly mixed, finely atomized air-fuel mixture to the intake manifold of the associated engine whereby a stoichemetric air-fuel mixture may be used thereby minimizing pollution problems and optimizing fuel consumption.
It is another object of the present invention to provide a carburetor which is of relatively simple construction; and may be produced most economically; and which is highly durable and reliable in operation.
It is an additional object of the present invention to provide a carburetor of the character stated which incorporates a component concurrently acting as one boundary of the sonic throat and serving as an accelerator pump thereby producing a highly integrated carburetor.